Group : Satellites
Status : Cancelled
Also Known As : National Polar-orbiting Operational Environment Satellite System
Origin : United States of America
Contractors : Northrop Grumman, Raytheon
Initial Operational Capability (IOC) : 2012
Total Production : 2
Unitary Cost : USD $2.8 billion

The National Polar-orbiting Operational Environment Satellite System (NPOESS) is the next generation American weather forecast satellite network. This program is sponsored by the Department of Defense (DoD), NASA and the Department of Trade. It is intended to provide highly reliable weather forecast information to many US government agencies.

The NPOESS contract was awarded to TRW (now Northrop-Grumman) teaming with Raytheon in August 2002. The entire program including logistics support and other services for its entire service life total cost was estimated as high as $4.5 billion, but DoD awarded a modification contract in February 2004 to Northrop-Grumman that could increase that figure to $4.8/4.9 billion.

The NPOESS network will consists of two satellites to be put into orbit in November 2009 (NPOESS C1) and June 2011 (NPOESS C2). The original contract awarded to TRW in 2002 established the C1 satellite to be put into orbit in March 2008 but that was shifted by the contract awarded in February 2004.

The NPOESS program also incorporates a new fiber optic network from Svalbard, mainland of Norway, to Tromso, United States of America. This network will provide NPOESS program with a high-speed data transfer channel of 155 Mbps from the Svalbard ground station, Norway.

The Svalbard ground station is so far north that it can see polar-orbiting satellites on every orbit. The huge amount of data gathered by NPOESS and legacy weather satellites is used to determine global sea surface wind speed and direction and to monitor solar mass ejections from the sun as well.

The NPOESS program includes an option to produce and then put into orbit four additional satellites in the period between 2012 and 2018. On 7 February 2005, Raytheon announced the completion of major development milestone on the NPOESS program. That was the qualification and testing of the third software increment for the command, control and communications segment (C3S) which will consist of more than 1.7 million lines of code.

The Visible Infrared Imaging Radiometer Suite (VIIRS) is a key NPOESS payload developed by Raytheon that will collect visible/infrared imagery and radiometric data on the atmosphere, clouds, earth radiation budget, clear-air land/water surfaces, sea surface temperature, ocean color, and low-light visible imagery. The sensor will offer dramatic spatial, spectral and radiometric performance improvements compared with current operational capabilities.

In early 2010 the Department of Defense, the Department of Commerce, and the National Aeronautics and Space Administration restructured the program and they will no longer jointly acquire NPOESS. The DoD allocated $5.8 billion out of $11.14 billion which is the initial program's cost. In 2011 the program's quantity was decreased to only two satellites.

The program was cancelled in 2010.